All-optical switching using a new photonic crystal directional coupler

In this paper all-optical switching in a new photonic crystal directional coupler is performed.  The structure of the switch consists of a directional coupler and a separate path for a control signal called “control waveguide”. In contrast to the former reported structures in which the directional couplers are made by removing a row of rods entirely, the directional coupler in our optical switch is constructed by two reduced-radius line-defect waveguides separated by the control waveguide. Furthermore, in our case the background material has the nonlinear Kerr property. Therefore, in the structure of this work, no frequency overlap occurs between the control waveguide mode and the directional coupler modes. It is shown that such a condition provides a very good isolation between the control and the probe signals at the output ports. In the control waveguide, nonlinear Kerr effect causes the required refractive index change by the presence of a high power control (pump) signal. Even and odd modes of the coupler are investigated by applying the distribution of the refractive index change in the nonlinear region of a super-cell so that a switching length of about 94 µm is obtained at the wavelength of 1.55 µm. Finally, all-optical switching of the 1.55 µm probe signal using a control signal at the wavelength of 1.3 µm, is simulated through the finite-difference time-domain method, where both signals are desirable in optical communication systems. A very high extinction ratio of 67 dB is achieved and the temporal characteristics of the switch are demonstrated

Application of simulation and machine learning in supply chain management: A synthesis of the literature using the Sim-ML literature classification framework

This is the final version. Available on open access from Elsevier via the DOI in this recordData availability: Data will be made available on request.Stochastic modeling techniques, such as discrete-event and agent-based simulation, are widely used in supply chain management (SCM) for capturing real-world uncertainties. Over the last decade, data-driven approaches like machine learning (ML) have also gained prominence in SCM, employing methods such as supervised learning (SL), unsupervised learning (UL), and reinforcement learning (RL). As supply chains grow in complexity, hybrid models combining simulation (Sim) and ML are becoming increasingly common, and the field stands to gain from a structured review of this literature. Towards this, we developed the Sim-ML Literature Classification Framework, which includes a hierarchical taxonomy comprising five SC criteria, 22 Sim-ML classes and over 75 Sim-ML subclasses. We applied this framework to synthesize 99 papers, revealing significant diversity in how Sim-ML models are used to address supply chain challenges. Key findings include the recognition of the breadth of study objectives, identifying various forms of model hybridization achieved by combining discrete/continuous simulation techniques with SL, UL, and RL approaches, and the data flow mechanisms such as sequential and feedback methods employed by the simulation and ML elements of the hybrid model. Our findings also identify some gaps in the literature; for example, optimization is rarely incorporated into Sim-ML models. Also, most studies present Sim-ML models for addressing problems in general supply chains, likely due to the lack of access to industrial data. The review also highlights that Industry 4.0 technologies, such as digital twins and blockchain, are underrepresented in current research, as are topics like sustainability and transportation. These gaps suggest significant opportunities for future research. We provide guidelines for practitioners on applying Sim-ML models to manage supply chain drivers, mitigate the impact of disruptions, and integrate emerging technologies. Our review serves as a valuable resource for researchers, practitioners, and students interested in leveraging Sim-ML

Epidemiological Aspects of Canine Dirofilariasis in the North of Iran

Background: Dirofilaria immitis is an important parasite in dog and other carnivores. Our objec­tive was study on incidence and periodicity of heartworm in north of Iran and using other meth­ods for its diagnosis in addition to Parasitology exam.Methods: This survey spanned two years, between 2006 and 2008. Blood samples were collected from 431 stray dogs distributed along north of Iran, the coastal areas of the Caspian Sea. The Knott's modified test was used for diagnosis of D. immitis and other filariae. Meanwhile, the periodic­ity of microfilaria in peripheral blood circulation was calculated and the imaging diagno­sis techniques of four dogs that had positive results were done.Result: Diagnostic parasitology results indicated that 16.01% of stray dogs were microfilaremic. Two different microfilariae were diagnosed: D. immitis in 13.69%, Dipetalonema reconditum in 1.86% and in 0.46% both of them. There was no statistically significant between infection to fiariae with sex and age of dogs. Also study on the periodicity of the presence of microfilaria in peripheral circulation showed that the highest rate of those was at 1 am and the lowest rate at 12 pm. Radiographic study showed distinctive signs with varied degrees of severity included: Tortu­ous and enlargement of main and lobar pulmonary artery, pulmonary parenchymal lesions and Right side heart enlargement that confirmed in electrocardiography. Also in echocardiographic images observed short parallel-sided images with the appearance of equal signs that indicated the pres­ence of the heartworm.Conclusion: These results showed that to obtain a reliable diagnosis of heartworm infection, imag­ing tests could support parasitological exams

All-optical switching using a new photonic crystal directional coupler

In this paper all-optical switching in a new photonic crystal directional coupler is performed.  The structure of the switch consists of a directional coupler and a separate path for a control signal called “control waveguide”. In contrast to the former reported structures in which the directional couplers are made by removing a row of rods entirely, the directional coupler in our optical switch is constructed by two reduced-radius line-defect waveguides separated by the control waveguide. Furthermore, in our case the background material has the nonlinear Kerr property. Therefore, in the structure of this work, no frequency overlap occurs between the control waveguide mode and the directional coupler modes. It is shown that such a condition provides a very good isolation between the control and the probe signals at the output ports. In the control waveguide, nonlinear Kerr effect causes the required refractive index change by the presence of a high power control (pump) signal. Even and odd modes of the coupler are investigated by applying the distribution of the refractive index change in the nonlinear region of a super-cell so that a switching length of about 94 µm is obtained at the wavelength of 1.55 µm. Finally, all-optical switching of the 1.55 µm probe signal using a control signal at the wavelength of 1.3 µm, is simulated through the finite-difference time-domain method, where both signals are desirable in optical communication systems. A very high extinction ratio of 67 dB is achieved and the temporal characteristics of the switch are demonstrated

EMon : embodied monitorization

Serie : Lecture Notes in Computer Science, vol. 5859The amount of seniors in need of constant care is rapidly rising: an evident consequence of population ageing. There are already some monitorization environments which aim to monitor these persons while they remain at home. This, however, although better than delocalizing the elder to some kind of institution, may not still be the ideal solution, as it forces them to stay inside the home more than they wished, as going out means lack of accompaniment and a consequent sensation of fear. In this paper we propose EMon: a monitorization device small enough to be worn by its users, although powerful enough to provide the higher level monitorization systems with vital information about the user and the environment around him. We hope to allow the representation of an intelligent environment to move with its users, instead of being static, mandatorily associated to a single physical location. The first prototype of EMon, as presented in this paper, provides environmental data as well as GPS coordinates and pictures that are useful to describe the context of its user

Improvements to the Ionizing Radiation Risk Assessment Program for NASA Astronauts

To perform dosimetry and risk assessment, NASA collects astronaut ionizing radiation exposure data from space flight, medical imaging and therapy, aviation training activities and prior occupational exposure histories. Career risk of exposure induced death (REID) from radiation is limited to 3 percent at a 95 percent confidence level. The Radiation Health Office at Johnson Space Center (JSC) is implementing a program to integrate the gathering, storage, analysis and reporting of astronaut ionizing radiation dose and risk data and records. This work has several motivations, including more efficient analyses and greater flexibility in testing and adopting new methods for evaluating risks. The foundation for these improvements is a set of software tools called the Astronaut Radiation Exposure Analysis System (AREAS). AREAS is a series of MATLAB(Registered TradeMark)-based dose and risk analysis modules that interface with an enterprise level SQL Server database by means of a secure web service. It communicates with other JSC medical and space weather databases to maintain data integrity and consistency across systems. AREAS is part of a larger NASA Space Medicine effort, the Mission Medical Integration Strategy, with the goal of collecting accurate, high-quality and detailed astronaut health data, and then securely, timely and reliably presenting it to medical support personnel. The modular approach to the AREAS design accommodates past, current, and future sources of data from active and passive detectors, space radiation transport algorithms, computational phantoms and cancer risk models. Revisions of the cancer risk model, new radiation detection equipment and improved anthropomorphic computational phantoms can be incorporated. Notable hardware updates include the Radiation Environment Monitor (which uses Medipix technology to report real-time, on-board dosimetry measurements), an updated Tissue-Equivalent Proportional Counter, and the Southwest Research Institute Radiation Assessment Detector. Also, the University of Florida hybrid phantoms, which are flexible in morphometry and positioning, are being explored as alternatives to the current NASA computational phantoms

Technology Roadmapping Application in Smart City's Development

Modern cities are changing to become more reliant upon technology for better personal, social, and economic outcomes for all citizens. The core of enabling a smart city plan relies on a comprehensive understanding of its drivers and technological aid requirements. Hence, technology roadmapping as one of the most effective approaches need to be considered to aligning the smart cities strategies with planning in the field of technology, while the focus on the most technology roadmapping studies has been limited to the development of industrial technology and product development. Thus, to support the achievement of the smart cities, this study aims to adapt and utilise Strategic Technology Alignment Roadmapping (STAR) methodology to guid and justify investment in smart city’s R&D projects to achieve the optimum project portfolio. The method is tested in a real case study, which shows how STAR methodology can be effective to implement throughout the worldwide smart cities development to support strategic technology investments

A new eco-friendly initiative for last food mile delivery in urban areas

The last food mile delivery involves the final step of delivering food products to the end customers. By developing e-commerce channels, home delivery is considered the final mile of food delivery. However, although home food delivery has received much welcome from consumers, it is still one of the costliest and most polluting segments in the food supply chain, and its optimisation is highly felt. Thus, this paper proposes a new initiative to reduce the environmental impacts of home food deliveries from retailers in urban areas. Last food mile models for both the conventional approach in which each retailer has its own dark store and for a proposed approach in which all retailers have only one common dark store for home food delivery are developed. A Vehicle Route Problem with Time Window (VRPTW) and heterogeneous fleet are developed to minimise both CO2 emission and transportation cost simultaneously and implemented using a simulated annealing algorithm that is programmed in MATLAB software. The obtained results revealed that the proposed initiative's application can significantly impact the reduction of both CO2 emission and transportation costs

Battery-operated Independent Radiation Detector Data Report from Exploration Flight Test 1

Citation: Bahadori AA, Semones EJ, Gaza R, Kroupa M, Rios RR, Stoffle NN, Campbell-Ricketts T, Pinsky LS, and Turecek D 2015 Battery-operated Independent Radiation Detector Data Report from Exploration Flight Test 1 NASA/TP-2015-218575 NASA Johnson Space Center: Houston, TX http://ston.jsc.nasa.gov/collections/TRS/397.refer.htmlThis report summarizes the data acquired by the Battery-operated Independent Radiation Detector (BIRD) during Exploration Flight Test 1 (EFT-1). The BIRD, consisting of two redundant subsystems isolated electronically from the Orion Multi-Purpose Crew Vehicle (MPCV), was developed to fly on the Orion EFT-1 to acquire radiation data throughout the mission. The BIRD subsystems successfully triggered using on-board accelerometers in response to launch accelerations, acquired and archived data through landing, and completed the shut down routine when battery voltage decreased to a specified value. The data acquired are important for understanding the radiation environment within the Orion MPCV during transit through the trapped radiation belts

Factors affecting intensive care units nursing workload

Background: The nursing workload has a close and strong association with the quality of services provided for the patients. Therefore, paying careful attention to the factors affecting nursing workload, especially those working in the intensive care units (ICUs), is very important. Objectives: This study aimed to determine the factors affecting nursing workload in the ICUs of the hospitals affiliated to Tehran University of Medical Sciences. Materials and Methods: This was a cross-sectional and analytical-descriptive study that has done in Iran. All nurses (n = 400) who was working in the ICUs of the hospitals affiliated to Tehran University of Medical Sciences in 2014 were selected and studied using census method. The required data were collected using a researcher-made questionnaire which its validity and reliability were confirmed through getting the opinions of experts and using composite reliability and internal consistency (α = 0.89). The collected data were analyzed through exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and using SPSS 18.0 and AMOS 18.0. Results: Twenty-five factors were divided into three major categories through EFA, including structure, process, and activity. The following factors among the structure, process and activity components had the greatest importance: lack of clear responsibilities and authorities and performing unnecessary tasks (by a coefficient of 0.709), mismatch between the capacity of wards and the number of patients (by a coefficient of 0.639), and helping the students and newly employed staff (by a coefficient of 0.589). Conclusions: The nursing workload is influenced by many factors. The clear responsibilities and authorities of nurses, patients' admission according to the capacity of wards, use of the new technologies and equipment, and providing basic training for new nurses can decrease the workload of nurses. © 2014, Iranian Red Crescent Medical Journal; Published by Kowsar Corp